Question

CGRect rect1 = backgroundImageView.frame;
NSLog(@"%f,%f,%f,%f",rect1.origin.x,rect1.origin.y,
                     rect1.size.width,rect1.size.height);

angle = -90.0;
moveX = 0;
moveY = 0.0;

CGFloat degreesToRadians = M_PI * angle / 180.0;
CGAffineTransform landscapeTransform =
      CGAffineTransformMakeRotation(degreesToRadians);
landscapeTransform =
      CGAffineTransformTranslate(landscapeTransform, moveX, moveY);
[backgroundImageView setTransform:landscapeTransform]; 

rect1 = backgroundImageView.frame;
NSLog(@"%f,%f,%f,%f",rect1.origin.x,rect1.origin.y,
                     rect1.size.width,rect1.size.height);

调试消息输出：

0.000000,0.000000,320.000000,480.000000
-80.000000,80.000000,480.000000,320.000000

为什么（x，y）变为（-80,80）？

Answer 1

设置转换时，backgroundImageView.center不会更改。如果父视图已经旋转，则应用变换后可以执行类似的操作。

backgroundImageView.center = backgroundImageView.superview.center;

无论哪种方式，为了您的目的，您应该调整中心而不是转换变换。

关于CGAffineTransformTranslate的问题

1 个答案: